Stem Cell Research Perseveres in the Midst of Funding Crisis

Chris Parker

The recent legal wrangling regarding the use or prohibition of the use of federal funds in scientific research utilizing human embryonic stem cells (hESCs) has generated significant uncertainty in the stem cell research community and is very unfortunate. The ruling places current hESC research in jeopardy and casts a cloud over future projects.

Congress should pass legislation to reverse this ruling and permit funding for hESC science. Even though the research community is moving toward the human induced pluripotent stem cell (iPSC) model introduced in 2007 by James Thomson, V.M.D., Ph.D., and Shinya Yamanaka, M.D., Ph.D., hESCs still retain utility as a benchmark for pluripotency and for differentiation protocols.

Under the hESC ban instituted by the Bush administration, federally funded research could continue on hESC lines that had been developed before August 2001, but federal funding of research on new hESC lines was prohibited.

The recent U.S. District Court decision, based on the Dickey-Wicker Amendment that Congress adds to budget legislation each year, is much more expansive. It prohibits federal funding of research on any hESC line regardless of when it was developed.

Ultimately, if the ban is not overturned by Congress or upon appeal to the U.S. Court of Appeals or the U.S. Supreme Court, then federally funded hESC research is in danger of grinding to a halt.

Numerous research projects will have to be redesigned or shut down. hESCs are the current stem cell benchmark for pluripotency to which all stem cell models are currently compared. At this time, hESCs are the stem cell benchmark for pluripotency to which all stem cell models are compared, and thus the lack of new hESC lines will ultimately inhibit progress of our understanding of pluripotency.

In addition, the ban could have a negative impact on the development of stem cell therapeutics since virtually all in development today are hESC-based. Thus the ban could potentially slow the development of important new therapeutic breakthroughs.

How does the ruling, if affirmed by a higher court, impact companies developing hESC-based products? hESC research will be able to proceed for now in instances where it is not directly federally funded. However, much hESC-based therapeutic R&D is based on the accumulated knowledge from federally funded basic research. Eventually, if the funding ban continues, then the decline on the rate of accumulation of new information on stem cell biology will begin to be a drag on therapeutic stem cell development as well.

Role of iPSCs

The uncertainty in funding will likely encourage researchers to accelerate the switch to iPSC technology. iPSCs have several advantages over hESCs. Most importantly, iPSCs provide a window on individual biology since both the phenotype and the genotype of the donor are known. This enables research on a variety of populations or patient subgroups that is essentially impossible to do with hESCs.

Secondly, supply of individual donors for reprogramming is theoretically unlimited since any individual could donate somatic cells that could be reprogrammed into iPSCs.

Finally, iPSCs do not engender political controversy. Like hESCs, iPSC lines are fully pluripotent; however, they are derived by reprogramming somatic cells. Therefore, federal funds should continue to be available for iPSC-based research even after the ruling.

Although science is migrating toward iPSCs and iPSC-derived differentiated cells as research models, hESCs still have a critical role to play and their long-term absence will negatively impact both basic and applied research.

hESCs are useful even in work with iPSCs, because they serve as a pluripotency benchmark to which all alternative stem cell models are measured. If the ban continues for a long period of time, progress in developing new research tools—even those based on iPSC technology—will slow, and the field could be weakened by this decision.

What can be done to dampen the negative impact of this legal wrangling on stem cell research, at least in the near term? The court decision will likely reinforce the migration of researchers and providers of stem cell-based research tools to iPSC-based technology.

One cannot assume that the recent court decision will ultimately be overturned. Therefore, cell-based research tool manufacturers will have to accelerate the development of new iPSC lines and deliver more iPSC-derived cell models into the hands of both pharmaceutical and academic researchers so that they can continue to proceed with their work.

Industry and academic scientists must work together to help expedite the transition of their research to new iPSC platforms. I believe that iPSC technology will enable them to continue their cutting-edge technology, while avoiding getting enmeshed in the politics of federal funding of stem cell research.

The court case is a very unfortunate one that will have a negative impact on scientists’ ability to further understand pluripotency and stem cell biology, particularly if the decision is upheld under appeal and Congress does not rescind or modify existing law.

iPSC-based cellular models are a viable alternative because they offer significant scientific utility compared to hESC-derived models. They also have the added advantage of avoiding the political uncertainty surrounding hESCs.